Encapsulate the deadlock detection functionality into 
a visitor class, and separate it from the wait-for graph
traversal code.

Use "Internal iterator" and "Visitor" patterns to 
achieve the desired separation of responsibilities.

Add comments.

and methods.

transactional SELECT and ALTER TABLE ...  REBUILD PARTITION".

Make open flags part of Open_table_context.
This allows to simplify some code and (in future)
enforce the invariant that we don't, say, request a back 
off on the table when there is MYSQL_OPEN_IGNORE_FLUSH 
flag.

 transactional SELECT and ALTER TABLE ...  REBUILD PARTITION".

Move declarations of sql_base.cc classes to sql_base.h
(previously declared in sql_class.h).
Became possible after a header file split.

transactional SELECT and ALTER TABLE ...  REBUILD PARTITION".

Remove unused code - TL_WRITE_ALLOW_READ thr_lock.c lock.

bug #46947 "Embedded SELECT without FOR UPDATE is causing 
a lock".

Fixed comments in tests. Improved comments and performance of
auxiliary scripts.

RENAME is allowed on views (not documented, broken)".

Adjusted test cases in funcs_1 suite after removing support
of ALTER TABLE RENAME for views.

bug #51263 "Deadlock between transactional SELECT and ALTER
TABLE ... REBUILD PARTITION" and has been causing compilation
error when server was built with NDB support.

is allowed on views (not documented, broken)".

Remove support of ALTER TABLE RENAME for views as:
a) this feature was not documented,
c) does not add any compatibility with other databases,
b) its implementation doesn't follow metadata locking
   protocol by accessing .FRM without holding any
   metadata lock,
c) its implementation complicates ALTER TABLE's code
   by introducing  yet another separate branch to it.

After this patch one can rename a view by using the
documented way - RENAME TABLE statement.

objects whose length is stored in a size_t type.

Post-merge fix: Pass the right parameter type to open_and_lock_tables.
Passing FALSE ensures that derived table handling is disabled, truncate
only operates on base tables.

Post-merge fix: Retrieve handler statistics to workaround quirks
of the archive storage engine.

The problem was that mdl_sync.test was failing sporadically,
due to fact that part of the test didn't take into account
effects of MyISAM's concurrent insert.

This patch solves the problem by making test case robust
against concurrent insert.

SELECT and ALTER TABLE ...  REBUILD PARTITION".

ALTER TABLE on InnoDB table (including partitioned tables)
acquired exclusive locks on rows of table being altered.
In cases when there was concurrent transaction which did
locking reads from this table this sometimes led to a
deadlock which was not detected by MDL subsystem nor by
InnoDB engine (and was reported only after exceeding
innodb_lock_wait_timeout).

This problem stemmed from the fact that ALTER TABLE acquired
TL_WRITE_ALLOW_READ lock on table being altered. This lock
was interpreted as a write lock and thus for table being
altered handler::external_lock() method was called with
F_WRLCK as an argument. As result InnoDB engine treated
ALTER TABLE as an operation which is going to change data
and acquired LOCK_X locks on rows being read from old
version of table.

In case when there was a transaction which already acquired
SR metadata lock on table and some LOCK_S locks on its rows
(e.g. by using it in subquery of DML statement) concurrent
ALTER TABLE was blocked at the moment when it tried to
acquire LOCK_X lock before reading one of these rows.
The transaction's attempt to acquire SW metadata lock on
table being altered led to deadlock, since it had to wait
for ALTER TABLE to release SNW lock. This deadlock was not
detected and got resolved only after timeout expiring
because waiting were happening in two different subsystems.

Similar deadlocks could have occured in other situations.
This patch tries to solve the problem by changing ALTER TABLE
implementation to use TL_READ_NO_INSERT lock instead of
TL_WRITE_ALLOW_READ. After this step handler::external_lock()
is called with F_RDLCK as an argument and InnoDB engine
correctly interprets ALTER TABLE as operation which only
reads data from original version of table. Thanks to this
ALTER TABLE acquires only LOCK_S locks on rows it reads.
This, in its turn, causes inter-subsystem deadlocks to go
away, as all potential lock conflicts and thus deadlocks will
be limited to metadata locking subsystem:

- When ALTER TABLE reads rows from table being altered it
  can't encounter any locks which conflict with LOCK_S row
  locks. There should be no concurrent transactions holding
  LOCK_X row locks. Such a transaction should have been
  acquired SW metadata lock on table first which would have
  conflicted with ALTER's SNW lock.
- Vice versa, when DML which runs concurrently with ALTER
  TABLE tries to lock row it should be requesting only LOCK_S
  lock which is compatible with locks acquired by ALTER,
  as otherwise such DML must own an SW metadata lock on table
  which would be incompatible with ALTER's SNW lock.

The problem was that TRUNCATE TABLE didn't take a exclusive
lock on a table if it resorted to truncating via delete of
all rows in the table. Specifically for InnoDB tables, this
could break proper isolation as InnoDB ends up aborting some
granted locks when truncating a table.

The solution is to take a exclusive metadata lock before
TRUNCATE TABLE can proceed. This guarantees that no other
transaction is using the table.

Incompatible change: Truncate via delete no longer fails
if sql_safe_updates is activated (this was a undocumented
side effect).

transactional SELECT and ALTER TABLE ... REBUILD PARTITION".

The goal of this patch is to decouple type of metadata
lock acquired for table by open_tables() from type of
table-level lock to be acquired on it.

To achieve this we change approach to how we determine what
type of metadata lock should be acquired on table to be open.
Now instead of inferring it at open_tables() time from flags
and type of table-level lock we rely on that type of metadata
lock is properly set at parsing time and is not changed
further.

FOR UPDATE is causing a lock".
 
This patch tries to address problems which were exposed 
during backporting of original patch to 5.1 tree.
 
- It ensures that we don't change locking behavior of simple
  SELECT statements on InnoDB tables when they are executed
  under LOCK TABLES ... READ and with @@innodb_table_locks=0.
  Also we no longer pass TL_READ_DEFAULT/TL_WRITE_DEFAULT 
  lock types, which are supposed to be parser-only, to 
  handler::start_stmt() method.
- It makes check_/no_concurrent_insert.inc auxiliary scripts 
  more robust against changes in test cases that use them
  and also ensures that they don't unnecessarily change 
  environment of caller.

The problem was that OPTMIZE TABLE was allowed to run on a table
in use by a transaction in a different connection. This caused
repeatable read to break.

This bug was fixed by the introduction of metadata locking, WL#4284.
OPTIMIZE TABLE will now be blocked until the transaction using the
table, has ended.

This patch contains a regression test added to innodb_mysql_lock.test
and no code changes.

That was a pure test issue -- filter implementation in Perl did not work
on some platform (the bug occurred on Windows Server 2008 with
Cygwin Perl 5.10.0).

in a multiquery packet): fix NDB test failures.

removing disabled line for rpl_row_create_table  due to Bug#45576. Anyway, the test is still there because of Bug#51574

pushing to next-mr-bugfixing from working branch

multiquery packet).

Background:

  - a query can contain multiple SQL statements;

  - the server frees resources allocated to process a query when the
    whole query is handled. In other words, resources allocated to process
    one SQL statement from a multi-statement query are freed when all SQL
    statements are handled.

The problem was that the parser allocated a buffer of size of the whole
query for each SQL statement in a multi-statement query. Thus, if a query
had many SQL-statements (so, the query was long), but each SQL statement
was short, ther parser tried to allocate huge amount of memory (number of
small SQL statements * length of the whole query).

The memory was allocated for a so-called "cpp buffer", which is intended to
store pre-processed SQL statement -- SQL text without version specific
comments.

The fix is to allocate memory for the "cpp buffer" once for all SQL
statements (once for a query).

approved):

3161 Vladislav Vaintroub       2010-04-29                 
 Bug#53196 : CMake builds don't support 'make tags' and 
'make ctags' targets.  
   - Added tags and ctags targets

for ALTER TABLE, LOAD DATA).

ROW_COUNT is now assigned according to the following rules:

  - In my_ok():
    - for DML statements: to the number of affected rows;
    - for DDL statements: to 0.

  - In my_eof(): to -1 to indicate that there was a result set.

    We derive this semantics from the JDBC specification, where int
    java.sql.Statement.getUpdateCount() is defined to (sic) "return the
    current result as an update count; if the result is a ResultSet
    object or there are no more results, -1 is returned".

  - In my_error(): to -1 to be compatible with the MySQL C API and
    MySQL ODBC driver.

  - For SIGNAL statements: to 0 per WL#2110 specification. Zero is used
    since that's the "default" value of ROW_COUNT in the diagnostics area.

type, which some time ago became part of Open_table_context class.
Apparently standalone enum type was erroneously re-introduced
during one of merges.

which was introduced by fix for bug 47459 "Assertion in
Diagnostics_area::set_eof_status on OPTIMIZE TABLE.

 - Update/fix file layouts for each package type, add new types for
   native package formats including deb, rpm and svr4.

 - Build all plugins, including debug versions

 - Update compiler flags to match current release

 - Add missing @VAR@ expansions

 - Install correct mysqclient library symlinks

 - Fix icc/ia64 builds

 - Fix install of libmysqld-debug

 - Don't include mysql_embedded

 - Remove unpackaged manual pages to avoid missing files warnings

 - Don't install mtr's test suite

with other merges from the old distribution-specific spec file.

 - update copyright notices

 - remove __os_install_post override, it was only necessary as a
   hack to build debuginfo packages - now that we no longer make
   them we can revert to the distribution macro which likely has
   other useful bits we might want

 - remove _unpackaged_files_terminate_build override, we want to
   know of any orphaned files

 - include native distribution support

 - no longer build separate debuginfo RPMs, instead just include
   debug/symbols in all binaries, which is more useful for support

 - include support for building commercial RPMs, requires a
   commercial source tree

 - remove cluster RPM support, we don't build them from this
   source tree

 - use CMake for building, and update package lists to match the
   new install layout/files.  Remove any options which were only
   useful for automake builds (e.g. yassl/zlib).

 - other minor cleanups

            via mysqld_safe

Plugin dir was set to a hard-coded path instead of relative the base dir.

This patch fixes this by using a path relative the basedir instead of the
plugin directory indicated by the configuration.

thd->in_multi_stmt_transaction() and thd->active_transaction().